default.nix

with import <nixpkgs> {};

stdenv.mkDerivation {
  name = "impurePythonEnv";

  buildInputs = [
    # these packages are required for virtualenv and pip to work:
    #
    python3Full
    python3Packages.virtualenv
    python3Packages.pip
    # the following packages are related to the dependencies of your python
    # project.
    # In this particular example the python modules listed in the
    # requirements.tx require the following packages to be installed locally
    # in order to compile any binary extensions they may require.
    #
    libffi
    openssl
  ];
  shellHook = ''
  # set SOURCE_DATE_EPOCH so that we can use python wheels
  SOURCE_DATE_EPOCH=$(date +%s)
  virtualenv venv
  virtualenv --no-setuptools venv
  export PATH=$PWD/venv/bin:$PATH
  pip install pipenv
  pipenv install
  pipenv shell
  '';
}